Optical sensor including disposable and reusable elements

ABSTRACT

An embodiment of the present disclosure provides a noninvasive optical sensor or probe including disposable and reusable components. The assembly of the disposable and reusable components is straightforward, along with the disassembly thereof. During application to a measurement site, the assembled sensor is advantageously secured together while the componentry is advantageously properly positioned.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/828,784, filed Aug. 18, 2015, which is a continuation of U.S. patentapplication Ser. No. 14/066,529, filed Oct. 29, 2013, which is acontinuation of U.S. patent application Ser. No. 12/829,276, filed Jul.1, 2010, which is a continuation-in-part of U.S. patent application Ser.No. 11/606,455, filed Nov. 29, 2006, and also claims priority benefitunder 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No.61/222,450, filed Jul. 1, 2009. The disclosures of each of the priorityapplications are incorporated by reference herein. Additionally, thisapplication relates to U.S. Pat. No. 6,920,345, issued Jul. 19, 2005,U.S. Pat. No. 7,225,007, issued May 29, 2007, U.S. application Ser. No.11/754,972, filed May 29, 2007, published as U.S. Patent ApplicationPublication No. 2007/0244378, and U.S. application Ser. No. 11/606,455,filed Nov. 29, 2006, published as U.S. Patent Application PublicationNo. 2007/0123763, the disclosures of which are incorporated in theirentirety by reference herein.

FIELD OF THE DISCLOSURE

The present disclosure relates to noninvasive optical sensors capable ofdetecting light attenuated by body tissue. More specifically, thedisclosure relates to the combination of reusable and disposablecomponents of such sensors.

BACKGROUND OF THE DISCLOSURE

Early detection of low blood oxygen is important in a wide range ofapplications, including patient monitoring, the fitness industry, homecare and the like. Noninvasive oximetry was developed to study and tomeasure, among other things, the oxygen status of blood. Pulseoximetry—a noninvasive, widely accepted form of oximetry—relies on asensor attached externally to a patient to output signals indicative ofvarious physiological parameters, such as a patient's blood oxygensaturation.

A pulse oximeter sensor generally includes one or more energy emissiondevices, such as specific wavelength emitting LEDs, and one or moreenergy detection devices. The sensor is generally attached to ameasurement site such as a patient's finger, ear, ankle, or the like,using an attachment mechanism such as a disposable tape, reusablehousing, a plastic or hook-and-loop fastening strap, or the like. Theattachment mechanism positions the emitters and detector proximal to themeasurement site such that the emitters project energy into the bloodvessels and capillaries of the measurement site, which in turn attenuatethe energy. The detector then detects that attenuated energy. Thedetector communicates at least one signal indicative of the detectedattenuated energy to a signal processing device such as an oximeter. Theoximeter generally calculates, among other things, one or morephysiological parameters of the measurement site.

High fidelity pulse oximeters capable of reading through motion inducednoise are disclosed in U.S. Pat. Nos. 6,770,028, 6,658,276, 6,157,850,6,002,952 5,769,785, and 5,758,644, which are assigned to MasimoCorporation (“Masimo”) and are incorporated by reference herein.Advanced physiological monitoring systems may incorporate pulse oximetryin addition to advanced features for the calculation and display ofother blood parameters, such as carboxyhemoglobin (HbCO), methemoglobin(HbMet) and total hemoglobin (Hbt), total Hematocrit (Hct), oxygenconcentrations and glucose concentrations, as a few examples. Advancedphysiological monitors and corresponding multiple wavelength opticalsensors capable of measuring parameters in addition to SpO₂, such asHbCO, HbMet and Hbt are described in at least U.S. patent applicationSer. No. 11/367,013, filed Mar. 1, 2006, titled Multiple WavelengthSensor Emitters and U.S. patent application Ser. No. 11/366,208, filedMar. 1, 2006, titled Noninvasive Multi-Parameter Patient Monitor,assigned to Masimo Laboratories, Inc. and incorporated by referenceherein. Further, noninvasive blood parameter monitors and correspondingmultiple wavelength optical sensors, such as Rainbow™ adhesive andreusable sensors and RAD57™ and Radical-7™ monitors for measuring SpO₂,pulse rate, perfusion index (PI), signal quality (SiQ), pulsevariability index (PVI), HbCO and HbMet, among other parameters, arealso available from Masimo.

Noninvasive oximetry sensors can be disposable, reusable, or somecombination thereof. Reusable sensors offer advantages of superior costsavings. However, reusable sensors are often available in a limitednumber of sizes even though patient measurement sites, such as fingersor toes, can have a much larger size distribution. Therefore, sometimesreusable sensors do not readily conform to each patient's attachmentsite. Disposable sensors on the other hand offer superior conformance tothe measurement area. However, disposable sensors are generally morecostly due to limited use of the relatively expensive sensor componentswhich could otherwise last for repeated uses.

Faced with the drawbacks of reusable and disposable sensors,manufacturers began designing a number of middle-ground sensors. Forexample, some manufacturers offer a reusable detector portion thatcouples to a disposable emitter portion. After a single use, thedisposable emitter portion is detached from the reusable detectorportion and discarded. While this design reuses some of the expensiveelectronic components, others are still discarded.

Another example of a middle-ground sensor includes a reusable “Y” typesensor, where a reusable emitter portion connects to one branch of the“Y” while a reusable detector portion connects to the other branch. Adisposable tape positions the two branches on a measurement site. Inthis design, the electronics are reusable; however, the multiple wirestend to be somewhat difficult to properly attach, especially with amoving patient.

Other examples of middle-ground sensors include a disposable tapesandwich where a reusable flexible circuit housing an emitter portionand a detector portion, are “sandwiched” between adhesive layers.Separation of such disposable tape sandwiches can be cumbersome. In yetanother example of a middle-ground sensor, the Assignee of the presentapplication disclosed a reusable flexible circuit is snapped into adisposable tape. In an embodiment of that disclosure, small pegs on theflexible circuit snap into mechanically mating elements on thedisposable tape. Grooves allow some longitudinal travel between thereusable portion and the disposable portion, thereby allowing for someself adjustment between components to account for differences in radialattachment requirements.

SUMMARY OF THE DISCLOSURE

However, even with the advances discussed in the foregoing, therecontinues to be a need for a commercially viable, straightforward,middle-ground solution that offers reusability of expensive electroniccomponents while maintaining some of the advantages of disposableattachment.

Accordingly, one aspect of an embodiment of the present disclosure is toprovide a sensor having reusable and disposable components. In anembodiment, the sensor advantageously includes a disposable componentstructured to provide a locking feature capable of reducing a chancethat the disposable and reusable components can separate when attachedor otherwise in close proximity to the body. In an embodiment, a lockingmechanism takes advantage of longitudinal displacement to engage whenthe reusable and disposable portions of the sensor are curved around themeasurement site (such as a finger). Separation of the reusable portionfrom the disposable portion is then advantageously complicated until thesensor is removed from the patient and the displacement is reversed.

A further aspect of an embodiment of this disclosure is that the aportion of the reusable sensor component, such as, for example, thefront portion or casing of the reusable sensor component can be attachedto and released from a corresponding front housing component on thedisposable component substantially vertically, substantiallyhorizontally, or angularly. As such, for example, the front casing ofthe reusable sensor can attach to and release from the disposablecomponent via the underside of the front casing (e.g., due to upwardpulling by the patient or medical personnel), the front of the casing(e.g., due to lateral pulling) or angularly through a portion of boththe underside and the front of the casing. This configuration allows forefficient, straightforward mating and separation of the reusable anddisposable sensor components. Moreover, strain on the connection betweenthe front portion of the reusable sensor component and the front housingof the disposable component, such as strain due to pulling by thepatient or medical personnel, is also advantageously reduced.

In a further embodiment, a memory device or information element isprovided as part of the disposable housing. An electrical contact ismade between the memory device and the reusable components to, forexample, ensure quality control in the disposable housing, provideinformation to the patient monitor about the type of sensor, type ofpatient, type of attachment mechanism or attachment position,information about operating characteristics of the sensor, productmanufacture or sale history, distributor history, amount of use,combinations of the same or the like.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the disclosure have been described herein. Ofcourse, it is to be understood that not necessarily all such aspects,advantages or features will be embodied in any particular embodiment ofthe disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings and the associated descriptions are provided toillustrate embodiments of the present disclosure and do not limit thescope of the claims.

FIG. 1 illustrates an exemplary block diagram of an oximeter systemincluding a sensor and a monitoring instrument, according to embodimentsof the disclosure.

FIG. 2 illustrates a perspective view of the sensor of FIG. 1, wherereusable and disposable components of the sensor are separated accordingto an embodiment of the disclosure.

FIGS. 3A-3B illustrate perspective views of the sensor of FIG. 2, wherethe components are connected in an assembly/disassembly position,according to an embodiment of the disclosure.

FIG. 4 illustrates a perspective side view of the sensor of FIG. 2,where the components are in an attached position, according to anembodiment of the disclosure.

FIG. 5A-5B illustrate top and bottom perspective views of a detectorcasing or housing of the reusable component, according to an embodimentof the disclosure.

FIG. 5C illustrates a front view of a detector casing or housing of thereusable component, according to an embodiment of the disclosure.

FIG. 6A-6B illustrate top and bottom perspective views of an emittercasing or housing of the reusable component, according to an embodimentof the disclosure.

FIG. 7 illustrates a perspective view of a front holding clip of thedisposable component, the clip being capable of mechanically mating withthe detector casing of FIG. 5, according to an embodiment of thedisclosure.

FIG. 8 illustrates a perspective view of the assembly/disassembly clipof the disposable component, the clip being capable of mechanicallymating with the emitter casing of FIG. 6, according to an embodiment ofthe disclosure.

FIG. 9 illustrates a top planar view of the disposable componentincluding the front holding clip and the assembly/disassembly clip ofFIGS. 7-8, according to an embodiment of the disclosure.

FIG. 10A illustrates an exploded view of the disposable component,according to an embodiment of the disclosure.

FIG. 10B illustrates an exploded view of the reusable component,according to an embodiment of the disclosure.

FIG. 11 illustrates top planar and side views of component placement ofconventional sensors.

FIG. 12 illustrates top planar and side views of component placementaccording to an embodiment of the disclosure.

FIG. 13 illustrates a top down planar view of a disposable sensor,according to an embodiment of the disclosure.

DETAILED DESCRIPTION

An embodiment of the present disclosure is a sensor with a reusablecomponent and a disposable component. The reusable component generallyincludes reusable relatively expensive electronic components of asensor, including, for example, the emitters and detector(s). In anembodiment, the emitters and the detector(s) are located in respectivecasings connected by a short flexible circuit. In an embodiment, adisposable component includes mechanically matable portions adapted tomechanically mate with the casings of the reusable component. In anembodiment, the casings of the reusable component mate with thedisposable component in a manner that provides an assembly/disassemblystate, and an attached state. During the assembly/disassembly state, acaregiver can readily and straightforwardly assemble the sensor byaligning the casings on the reusable component and the mechanicalhousings of the disposable component and snapping or sliding themtogether. In an embodiment, the forward casing of the reusable componentis aligned with the forward clip on the disposable component andsnapping occurs by lightly pressing on the components vertically,horizontally, or at an angle while on a flat surface or supported fromunderneath by, for example, the hand of the assembler. In an embodiment,the rearward housing generally vertically accepts the rearward casing insuch a way that the rearward casing can move horizontally with respectto the rearward housing; however, one of the housings, such as, forexample, the forward housing or clip accepts the casing in such a way asto keep the forward casing generally immobile, in a fixed position withrespect to the housing, during use.

Disassembly is also relatively straightforward, as the caregiver mayadvantageously laterally pull on the reusable component, and therearward casing extracts from the mechanically mated housing of thedisposable element. Continual lifting and/or lateral pulling thensimilarly extracts the forward casing from the mechanically matedhousing of the disposable element. In an embodiment, the forward casingincludes at least one opening which receives and generally snaps onto atleast one electrical contact of the forward housing. Moreover, each ofthe openings can extend along a portion of the underside of the casingand along a portion of the front of the casing. As such, the electricalcontacts of the housing can attach to and release from the openings viathe underside of the casing (e.g., due to upward pulling by the patientor medical personnel), the front of casing (e.g., due to lateralpulling) or angularly, through a portion of the underside and a portionof the front. The at least one opening of certain embodiments isconfigured to receive at least one prong of the disposable attachmentsuch that the at least one prong is slidable within the opening duringmating of the disposable attachment and the second casing. For example,the at least one opening may comprise a channel extending along one ormore surfaces of the second casing, such as along a portion of a bottomsurface of the second casing and a portion of the front surface of thesecond casing. The configurations described above thereby allow forefficient, straightforward attachment and release of the forward casing.Moreover, the risk of strain being placed on the sensor components suchas strain to due lateral and/or upward pulling by the patient or medicalpersonnel is advantageously reduced. In an embodiment, the flexiblecircuit between the forward and rearward casing may be reinforced inorder to withstand multiple disassembly stresses or forces occurringfrom the lifting of the reusable wire. In an embodiment, pressing thedisposable portion onto a flat surface while lifting the reusableportion aids in the disassembly process.

disposable portion includes structures designed to attach the sensor toa measurement site. In an embodiment, the disposable portion comprises aflexible tape having an adhesive side capable of removably adhering tothe measurement site. In an embodiment where the disposable portionwraps around a measurement site, the act of bending the flexible circuitadvantageously causes the assembly/disassembly clip to recess into themechanically mated portion of the disposable housing, thereby reducingthe likelihood of disassembly during application to a measurement site.In an embodiment, the sensor components are locked together through thelongitudinal displacement of the clip with respect to the disposablehousing. In such an embodiment, a stop diminishes the capacity of theclip to move vertically, thereby locking it into place. In thisembodiment, removing the adhesive from the measurement site andstraightening the sensor components unlocks the reusable and disposablecomponents.

In an embodiment, the assembly also electrically connects electroniccomponents of the disposable portion with those of the reusable portion.In an embodiment, the disposable portion includes an information elementor memory device, such as, for example, a resistor, a single wireaddressable memory device, such as those EPROMs or EEPROMs commerciallyavailable from Dallas Semiconductor, other memory or processing devices,combinations of the same, or the like. The information element mayinclude data accessibly by an attached patient monitor to accomplishquality control, monitor configuration, sensor use monitoring,combinations of the same, or the like.

Still other advantages of embodiments of the present disclosure includeproportionally positioning of the mechanically mating housings toprovide for optical alignment between the emitters and detector.Moreover, in embodiments including the disposable tape, the tape mayadvantageously be scored to assist the caregiver in proper alignmentwith the body tissue at the measurement site.

To facilitate a complete understanding of the disclosure, the remainderof the detailed description describes the disclosure with reference tothe drawings. Corresponding parts refer to corresponding elements andthe leading digit indicates the figure in which that element firstappears.

General Design

FIG. 1 presents an exemplary block diagram of the components generallyfound in an oximeter sensor, according to an embodiment. For example,FIG. 1 shows as oximeter system 100 including sensor 102, cable 170, andmonitor 172. The sensor 102 includes one or more emitters 174 forirradiating body tissue with light, and one or more detectors 176capable of detecting the light after attenuation by the tissue. Thesensor 102 also includes an information element 136 such as an EPROM.The sensor 102 also includes a plurality of conductors communicatingsignals; including emitter drive signal conductors 180, detectorcomposite signal conductors 182, and EPROM conductors 184. According toan embodiment, the sensor conductors 180, 182, 184 communicate theirsignals to and from the monitor 172 through cable 170.

Although disclosed with reference to the cable 170, a skilled artisanwill recognize from the disclosure herein that the communication to andfrom the sensor 106 may advantageously include a wide variety of cables,cable designs, public or private communication networks or computingsystems, wired or wireless communications, combinations of the same, orthe like.

The information element 136 may comprise an EPROM, an EEPROM,combinations of the same, or the like. In general, the informationelement 136 may include a read-only device or a read and write device.The information element may advantageously also comprise a resistor, anactive network, or any combination of the foregoing. The remainder ofthe present disclosure will refer to such possibilities as simply aninformation element for ease of disclosure.

The information element 136 may advantageously store some or all of awide variety of data and information, including, for example,information on the type or operation of the sensor 104, type of patientor body tissue, buyer or manufacturer information, sensorcharacteristics including the number of wavelengths capable of beingemitted, emitter specifications, emitter drive requirements,demodulation data, calculation mode data, calibration data, softwaresuch as scripts, executable code, or the like, sensor electronicelements, sensor life data indicating whether some or all sensorcomponents have expired and should be replaced, encryption information,or monitor or algorithm upgrade instructions or data. The informationelement 136 may advantageously configure or activate the monitor,monitor algorithms, monitor functionality, or the like based on some orall of the foregoing information. For example, without authorized dataaccessibly on the information element 136, quality control functions mayinhibit functionality of the monitor. Likewise, particular data mayactivate certain functions while keeping others inactive. For example,the data may indicate a number of emitter wavelengths available, whichin turn may dictate the number and/or type of physiological parametersthat can be monitored or calculated.

FIG. 1 also shows the monitor 172 comprising one or more processingboards 186 communicating with one or more host instruments 188.According to an embodiment, the board 186 comprises processing circuitryarranged on one or more printed circuit boards capable of beinginstalled in specialized monitoring equipment or distributed as an OEMcomponent for a wide variety of patient monitoring equipment. As shownin FIG. 1, the board 186 includes a front end signal conditioner 190, asensor controller 194, a digital signal processor or microcontroller192, and a memory reader 1102. In an embodiment, the processor 192instructs the sensor controller 194 to output one or more drive signalscapable of causing the emitters 174 to activate. The front end 190receives detector output indicating detection of light from the emitters174 attenuated by body tissue of the measurement site. The front end 190conditions the signal and outputs the signal and/or signal data to theprocessor 192. The processor 192 executes calculations adapted todetermine values and/or indications or physiological parameters, trendsof the parameters, alarms based on the parameters or the trends orcombinations of trends and/or parameters, or the like. In addition, thereader 1102 is capable of retrieving information stored on informationelement 136. The reader 1102 or the processor 192 may advantageouslydecrypt such information to the extent desired.

In an embodiment, the host instrument 188, communicates with theprocessor 192 to receive signals indicative of the physiologicalparameter information calculated by the processor 192. The hostinstrument preferably includes one or more display devices 196 capableof providing indicia representative of the calculated physiologicalparameters of the tissue at the measurement site. Such display devices196 may be controlled by a monitor controller 198 that accepts signalsfrom processor 192. In an embodiment, monitor controller 198 may alsoaccept signals from user interface 1100. Such signals may be indicativeof various display options for configuring the output to display 196. Inan embodiment, the host instrument 188 may advantageously be capable ofdisplaying one or more of a pulse rate, plethysmograph data, perfusionquality, signal or measurement quality, values of blood constituents inbody tissue, including for example, SpCO, functional or fractional SpO₂,or the like. In other embodiments, the host instrument 188 is capable ofdisplaying values for one or more of SpMet, HbO₂, Hb, HbCO, HbMet, Hct,blood glucose, bilirubin, or the like. In still additional embodiments,the host instrument 188 is capable of displaying trending data for oneor more of the foregoing measured or determined data. Moreover anartisan will realize from the disclosure herein many display options forthe data are available.

In an embodiment, the host instrument 188 includes audio or visualalarms that alert caregivers that one or more physiological parametersare falling below predetermined safe thresholds, and may includeindications of the confidence a caregiver should have in the displayeddata. In further embodiments, the host instrument 188 may advantageouslyinclude circuitry capable of determining the expiration or overuse ofcomponents of the sensor 102, including for example, reusable elements,disposable elements, or combinations of the same.

Although disclosed with reference to particular embodiment, an artisanwill recognize from the disclosure herein many variations of theinstrument 172. For example, in a broad sense, the instrument 172accepts data from the sensor 102, determines values for one or moreparameters, trends, alarms or the like, and outputs them to an interfacesuch as a display.

Sensor Configuration

FIG. 2 illustrates an embodiment of sensor 102, having reusablecomponent 204 and disposable component 206. The components are showndetached. FIG. 3 shows a very similar perspective drawing, but withreusable component 204 and disposable component 206 in their attached,assembled state. Returning to FIG. 2, the reusable component 204comprises an emitter casing 208, a detector casing 210, and a flexiblecircuit 212. The emitter casing 208 comprises one or more emissiondevices (not shown) operable to emit light at multiple wavelengths, suchas red and infrared. Detector casing 210 houses one or more detectors(not shown), such as a photodiode detector. In an embodiment, a flexiblecircuit 212 connects the emitter casing 208 and detector casing 210. Ina preferred embodiment, the flexible circuit 212 is housed in aprotective cover and extends beyond the emitter casing 208. An artisanwill understand from the disclosure herein that the emitter and detectorelectrical components may advantageously be housed in the casingsdisclosed or simply reversed from the foregoing disclosure. In anembodiment, the flexible circuit 212 and/or cabling extendssignificantly beyond the casings to advantageously remove any cableattachment mechanisms from the proximity of the tissue site.

The reusable component 204 of certain embodiments also includes a sensorconnector 203 configured to mate with a monitor connector (not shown).The sensor connector 203 and monitor connector are advantageouslyconfigured to be straightforwardly and efficiently joined with anddetached from one another. Embodiments of sensor and monitor connectorshaving similar connection mechanisms are described in U.S. patentapplication Ser. No. 12/248,856 (hereinafter referred to as “the '856application”), filed on Oct. 9, 2008, and published as U.S. PatentApplication Publication No. 2009/0099423, which is incorporated in itsentirety by reference herein. For example, the sensor connector 203includes a mating feature 213 which mates with a corresponding feature(not shown) on the monitor connector. The mating feature 213 may includea protrusion which engages in a snap fit with a recess on the monitorconnector. In certain embodiments, the sensor connector 203 can bedetached via one hand operation, for example. Examples of connectionmechanisms which are incorporated by reference herein may be foundspecifically in paragraphs [0042], [0050], [0051], [0061]-[0068] and[0079], and with respect to FIGS. 8A-F, 13A-E, 19A-F, 23A-D and 24A-C ofthe '856 application, for example, which is part of the incorporateddisclosure thereof. The sensor system 200 measures one or morephysiological parameters of the patient, such as one of thephysiological parameters described above.

In addition, the sensor connector 203 and monitor connector 209 mayadvantageously reduce the amount of unshielded area in and generallyprovide enhanced shielding of the electrical connection between thesensor and monitor in certain embodiments. Examples of such shieldingmechanisms which are incorporated by reference herein are disclosed inthe '856 application in paragraphs [0043]-[0053], [0060] and withrespect to FIGS. 9A-C, 11A-E, 13A-E, 14A-B, 15A-C, and 16A-E, forexample, which again is part of the incorporated disclosure thereof.

FIG. 2 also shows the disposable component 206 including a base 214, anassembly/disassembly clip 216 and a front holding clip 218, the clipseach adapted to accept the emitter casing 208 and detector casing 210,respectively. In the preferred embodiment, front holding clip 218includes a front stop 220. Front stop 220 is advantageous for a numberof reasons. It helps reduce the likelihood that the reusable component102, and in particular detector casing 210, will slide forward in thefront holding clip 218 during assembly or use. In addition, in anembodiment where the stop 220 comprises plastic or other liquidresistant material, the stop 220 provides a liquid resistant connectionbetween the detector casing 210 and front holding clip 218, reducing thelikelihood of sensor contamination and electrical shorts. Rubber or asimilar material may be used in an embodiment to compose such a frontstop 220.

FIG. 3A shows detector casing 210 clipped or snapped into front holdingclip 218. In an embodiment, a protrusion 211 (FIG. 5A) on a tip of thecasing 210 mates with a corresponding recess (not shown) on the frontstop 220. While shown as a circular protrusion 211 and a circularrecess, the components may include a variety of shapes such as, forexample, rectangular, square, triangular and the like. Moreover, inother embodiments, the components may be reversed and the holding clip218 may include a protrusion 211 and the casing 210 may include therecess. An artisan will recognize from the disclosure provided hereinthat any mechanically mating or male-female like mechanical connection,or reversals thereof may assist in guiding the casing 210 into the clip218. This allows the front stop 220 to reduce horizontal movement of thedetector casing 210, and helps reduce vertical release of the detectorcasing unless pulled from, for example, the cable. In anotherembodiment, a tip of the casing 210 may slide below a portion of thefront stop 220, such as, for example, a generally hooded portion (notshown) of the front stop 220. FIG. 3 also shows the front stop 220 witha generally rounded shape and including few, if any, sharp edges. Suchan embodiment advantageously reduces damage to a patient or the sensorif the patient tries to scratch body tissue using the edges of theassembled sensor, or if the sensor is dropped, banged against somethingwhile worn, or the like. This is particularly useful when used with burnvictims or other patients whose skin may damage easily.

FIG. 3B highlights the ease of assembly. The disposable portion 206 isset on a surface or held in the one hand. The caregiver then aligns afront tip of casing 210 and guides it into front holding clip 218. Thecasing 210 including rounded wings 531 (FIG. 5) that mechanicallyassociate with rounded side walls 739 (FIG. 7). These mechanicalstructures allow the casing 210 to slide and/or snap into place. Oncecasing 210 is in place, casing 208 aligns vertically and simply slidesdown, with tabs 262 (FIG. 6) sliding into slots 222 (FIG. 8) on a sideof assembly/disassembly clip 216. In an embodiment, the flexible circuitportion 212 between the casings 208 and 210 may bulge slightly.

FIG. 3B shows the emitter casing 208 after it has been slid ontoassembly/disassembly clip 216. With the reusable sensor component 204and the disposable sensor component 206 in a generally flat position andunattached position, the emitter casing 208 remains vertically mobile upthrough slots 222 of assembly/disassembly clip 216 and horizontallymobile through holding regions 224. When the sensor 102 is wrappedaround a measurement site 426, such as a finger, as shown in FIG. 4,emitter casing 208 slides forward in assembly/disassembly clip 216 dueto the tension from flexible circuit 212 and detector casing 210 beingsubstantially immobile in front holding clip 218. Tabs 262 (FIG. 6)slide away from their original positions underneath slots 222 (FIG. 8)to positions within the holding regions 224 (FIG. 8). Holding regions224 prevent emitter casing 208 from moving vertically or further forwardby restricting tabs 262. As stated before, the tension from flexiblecircuit 212 when it is wrapped around a measurement site 426 preventsthe emitter casing 208 from moving horizontally backwards when wrappedaround a measurement site. The immobility of casing 210, combined withthe tabs 262 sliding away from underneath the slots 222 to within theholding regions 224, effectively secure the reusable sensor component204 with respect to disposable component 206, with the emittersappropriately position with respect to the detector. Thus, realignmentthrough release of tension, i.e., removing the sensor from an attachmentsite and straightening it out, ensure straightforward disassembly of thesensor components. Although shown using tabs 262 and slots 222, askilled artisan will recognize from the disclosure herein a wide varietyof mechanical mechanisms that ensure reliable attachability when thesensor is applied to the tissue site and straightforwardassembly/disassembly when the sensor is removed. For example, one ormore detents that snap closed beyond a catch and are released throughpinching could be used to secure the reusable portion 104 to thedisposable portion 106.

As alluded to previously, FIG. 4 depicts sensor 102 as would be seenwhen in use on a measurement site 426. In this case, the measurementsite is a finger, but other sites such as a toe, ear, wrist or ankle mayalso work. Disposable component 206 and reusable component 204 areattached, and reusable component 204 is in the assembled and attachedposition. Longitudinal tension on the flexible circuit 212 from thediffering radius between the tape and the flex circuit has pulled theemitter casing 208 forward, placing tabs 262 within the holding regions224. FIG. 4 shows that, in an embodiment, emitter casing 208 is rearwardwith respect to assembly/disassembly clip 216 when in the unattachedposition (FIG. 3B), but the front of emitter casing 208 is forward withrespect to the assembly/disassembly clip 216 when in the attachedposition (FIG. 4).

FIGS. 5A-5C show close up top and bottom perspective and front views ofan embodiment of the detector casing 210, respectively. The detectorcasing 210 includes bottom 540, front 541, top 542 and rear 543surfaces. The detector casing 210 includes electrical contact acceptors528. In an embodiment, electrical contact acceptors 528 extend along aportion of the bottom 540 and along a portion of the front 541 of thedetector casing 210. The electrical contact acceptors 528 may also bereferred to as openings 528 and include conductive material that can beconnected to a wire in flexible circuit 212. As shown, the front portion529 of the detector casing 210 may include a cutout such that frontportion 529 sits on a raised step 733 portion of the front holding clip218 (see FIG. 7). Buttons 530 found on a side of the detector casing 210are, in the preferred embodiment, generally hemispherical protrusionsadapted to sit in depressions or holes 738 found on front holding clip218 (see FIG. 7). The detector casing 210 further includes opening 552(FIG. 5B). The detector casing 210 can be configured to cooperate withopening 732 (FIG. 7) of the front sensor clip 218 to allow lightattenuated by the patient's tissue to reach the detector electronics(not shown) housed by the detector casing 210. In various embodiments,the opening 552 can be substantially rectangular, as shown, or,alternatively, substantially circular, ovular, or some other shape.

FIG. 7 shows a close up perspective view of an embodiment of the frontholding clip 218, again to show detail less easily seen in smallerfigures. While most of the front sensor clip 218 may be made of plasticor some other rigid material, the preferred embodiment has front stop220 made of plastic as has been discussed. Opening 732 is also shownhere and may be a hole through front holding clip 218 or may includegenerally transparent material that will allow light from the LEDs toenter the tissue at the measurement site and allow light energy to beread by the photodiode. Having window 732 be transparent material willallow the sensor to obtain readings while keeping the LEDs andphotodiode from becoming contaminated. Other optical filters or the likecould also be housed in window 732. Additionally, in variousembodiments, a transparent material, optical filter or other coveringmay be provided to one or more of the opening 552 of the detector casing210, opening 662 of the emitter casing 208 and opening 842 of the rearsensor clip 216. In yet other embodiments, one or more of the variousopenings 552, 662, 742, 842 may comprise more than one opening.

Located inside front stop 220 are conducting prongs 734. Conductingprongs 734 are adapted to fit into electrical contact acceptors 528. Inan embodiment, the conducting prongs 734 close the circuit with theinformation element 136. When the detector casing 210 clips into thefront holding clip 218 and front stop 220, the conducting prongs 734slide into electrical contact with acceptors 528. The completed circuitallows the sensor 102, and in turn an oximeter, to communicate withinformation element 136. In an embodiment, the openings 528 of thedetector casing 210 receive and generally snap onto the conductingprongs 734 of the front holding clip 218. Moreover, because the openings528 extend along a portion of the bottom 540 of the casing and along aportion of the front 541 of the casing 210, the conducting prongs 734 ofthe front stop 220 can attach to and release from the openings via theunderside 540 of the casing 210 (e.g., due to upward pulling by thepatient or medical personnel), the front 541 of casing 210 (e.g., due tolateral pulling) or angularly through both the underside 540 and thefront 541 of the casing 210. Such configurations thereby allow forefficient, straightforward attachment and release of the forward casing210. In addition, in certain embodiments, the at least one opening 528of certain embodiments is configured to receive one or more of theprongs 734 such that the at least one prong 734 is slidable within theopening 528 during mating of the disposable attachment and the secondcasing 210. As shown, the at least one opening 528 may comprise achannel extending along one or more surfaces of the second casing 210,such as along a portion of a bottom surface 540 of the second casing 210and a portion of the front surface 541 of the second casing 210.Depressions or holes 738 are located on the interior of front holdingclip 218. They are preferably generally hemispherical depressionssimilar in size to buttons 530, so as to accept buttons 530, and holddetector casing 210 in a substantially immobile position relative tofront holding clip 218. Thus, a straightforward snap-in snap-outfriction fit is accomplished using buttons 530 and depressions 738.

FIGS. 6A-6B show close up top and bottom perspective views of emittercasing 208. Rear pegs 660 are located on a side of emitter casing 208.When tabs 262 slide down slots 222 of assembly/disassembly clip 216,rear alignment pegs 660 slide down behind assembly/disassembly clip 216.Rear pegs 660 provide structural support integrity once emitter casing208 has slid into a locking position by coming into position underneathrear portions 840 in assembly/disassembly clip 216 (See FIG. 8). Theemitter casing 208 further includes emitter casing opening 662 (FIG.6B). The opening 662 of the emitter casing 208 can be configured tocooperate with opening 842 (FIG. 8) of the rear sensor clip 216 to allowlight emitted from the emitter (not shown) housed within the emittercasing 210 to reach, for example, the patient's skin at the measurementsite. In various embodiments, the opening 662 can be substantiallyrectangular, as shown, or, alternatively, substantially circular,ovular, or some other shape.

FIG. 8 illustrates a close-up perspective view of a assembly/disassemblyclip 216 according to the preferred embodiment. As discussed emittercasing 208, slides down into assembly/disassembly clip 216 with tabs 262passing through slots 222 and rear pegs 660 passing behindassembly/disassembly clip 216. As emitter casing 208 slides forward dueto pull from application to a user, tabs 262 generally restrictover-forward movement or any vertical movement by abutting the surfaceof the clip 216 above holding regions 224. Assembly/disassembly clip 216also has a window 842 that may be, for example, substantially similar towindow 732 on the front holding clip 218.

FIG. 9 shows a top down view of the disposable sensor element. As shownin FIG. 9, the assembly/disassembly clip 216 and the slots 222 allowvertical entry of the tabs 262 and the emitter casing 208. Moreover,FIG. 9 shows windows 842 and 732 in assembly/disassembly clip 216 andfront holding clip 218, respectively. FIG. 9 also shows windows 944 and946. Windows 944, 946 are included in the base 214. Like the openings732, 842, windows 944, 946 may be holes through base 214, or they may beof a material allowing free light transmission. Windows 944, 946generally align with one or more of the openings 552, 662, 732 and 842to provide optical access to the measurement site for the emitters anddetectors of the sensor. FIG. 9 also shows the contact prongs 734 on theinsides of front stop 220. The contact prongs of the illustratedembodiment are positioned on the raised step portion 733 of the holdingclip 218. The contact prongs 734 connect the reusable sensor component204 to the information element 136, which may be variously utilized suchas for storing information relating to the sensor's manufacturer or thelike.

Manufacture

FIG. 10A illustrates an exploded view of an embodiment of disposablesensor component 206. As shown in FIG. 10A, disposable sensor component206 comprises a plurality of layers. For example, disposable sensorcomponent 206 includes a base tape 1038. This base tape 1038 ispreferably transparent polyethylene approximately 0.001 inches thick.Such material can be purchased from various sources, such as ProductNumber 3044 from Avery Dennison Medical of 7100 Lindsey Dr., Mentor,Ohio, 44060. As with all dimension recitations herein, an artisan willrecognize from the disclosure herein that the dimensions of a particularlayer may advantageously be redesigned according to various designdesires or needs, and layers may be added or combined without departingfrom the scope of the present disclosure.

A second layer comprises a tape or web layer 1040. This layer ispreferably white polypropylene also approximately 0.001 inches thick.One potential source for this material is Scapa North America, 540 NorthOak Street, Inglewood, Calif., 90302, specifically product number P-341.Tape layer 1040 also has windows 1054 that allow light energy emanatingfrom the sensor emitters to pass through this layer to the measurementsite 426 and also allows the light to pass through to the detector. Thewindows 1054 may be holes, transparent material, optical filters, or thelike. In the preferred embodiment, base tape 1038 does not have windows1054. Base tape 1038 is preferably generally clear as discussed above.This allows light to pass through the tape from the sensor, while alsogenerally reducing contamination of the sensor components. Disposablecomponent 206 also includes clip 218 and assembly/disassembly clip 216.In an embodiment, a pair of polyester film segments 1042 sandwich theclips 216, 218 in place. In an embodiment the polyester film segments1042 are generally clear and approximately 0.003 inches thick. Polyesterfilm segments 1042 also include slots 1044 to allow the verticalelements of assembly/disassembly clip 216 and front holding clip 218 toprotrude therefrom and to allow polyester film segments 1042 to sitrelatively flatly against the bases of assembly/disassembly clip 216 andfront holding clip 218. In other embodiments, the polyester filmsegments 1042 include one integral segment or more than two separatesegments. Front stop 220 may be connected to the vertical elements offront holding clip 218 with polyester film segments 1042 therebetween.In an embodiment, information element 136 resides within front stop 220,preferably affixed in place by adhesives and/or mechanical structure.For example, the front stop 220 may house the information element 136 ina depression, slot or cavity of the front stop 220. Such a configurationmay improve the tamper resistance so that the information element 136 isless likely to be disabled, damaged, replaced or removed, for example.

In certain embodiments, the disposable portion 206 includes a bottomliner layer (not shown). The bottom liner layer may be affixed to theunderside of the base tape 1038, for example. In an embodiment, the basetape 1038 includes adhesive for attaching the disposable component 206to the patient and the bottom liner layer is configured to peel off andexpose the adhesive layer. In another embodiment, the bottom liner layeritself includes adhesive for attaching the disposable component 206 tothe patient.

In other embodiments, the disposable portion 206 also includes one ormore light-blocking layers. For example, the disposable portion 206 mayinclude a first light-blocking layer preferably made of metalizedpolypropylene approximately 0.002 inches thick. This is a commerciallyavailable product available, for example, as Bioflex™ RX48P. The firstlight-blocking layer can include one or more cut-outs adapted to acceptportions of the disposable portion 206 such as, for example, theassembly/disassembly clip 216 and front holding clip 218. The firstlight-blocking layer increases the likelihood of accurate readings bypreventing the penetration to the measurement site of any ambient lightenergy (light blocking) and the acquisition of nonattenuated light fromthe emitters (light piping). In an embodiment, above the light blockinglayer is an opaque branding layer also having cut-outs adapted to acceptportions of the disposable portion 206 such as, for example, theassembly/disassembly clip 216 and the front holding clip 218. Thisbranding layer may advantageously comprise manufacturer's logos,instructions or other markings. Disposable sensor component 206 alsocomprises face tape 1050. This face tape 1050 is preferably a clear filmapproximately 0.003 inches thick and may be obtained commerciallythrough companies such as 3M (product number 1527ENP), located in St.Paul, Minn., 55144. Face tape 1050 includes cut-outs 1052 adapted toaccept assembly/disassembly clip 216 and front holding clip 218. In anembodiment, branding information such as manufacturer's logos,instructions or other markings may be included on the face tape 1050instead of or in addition to on the branding layer.

FIG. 10B illustrates an exploded view of a reusable component 204,according to an embodiment of the disclosure. Upper and lower portionsof the emitter casing 208 mate about a portion 1020 of the reusablecomponent 204 to enclose emitter electronics 1010. In addition, upperand lower portions of the detector casing 210 mate about a portion 1022of the reusable component 204 to enclose detector electronics 1012. Aswill be appreciated by those of skill in the art from the disclosureprovided herein, the emitter casing 208 and the detector casing 210 mayhouse one or more other components such as one or more other electricalcomponents as appropriate. For example, the detector casing 210 mayinclude one or more wires. In another embodiment, the detector casing210 houses one or more electrical shielding components which provideenhanced signal noise protection for the relatively sensitive detectorsignals.

Additional Advantages

FIG. 11 illustrates a disposable sensor highlighting issues relating tosensor positioning. Generally, when applying the sensor of FIG. 11, acaregivers will split the center portion between the emitter anddetector around, for example, a finger or toe. This may not be ideal,because as shown, it places the emitter 174 and detector 176 in aposition where the optical alignment may be slightly or significantlyoff.

FIG. 12 illustrates an embodiment of the disposable component 206including scoring line 1258. Scoring line 1258 is particularlyadvantageous, because it aids in quick and proper placement of thesensor on a measurement site 426. Scoring line 1258 lines up with thetip of a fingernail or toenail in at least some embodiments, using thosebody parts as the measurement site. FIG. 12 also illustrates thedisposable component 206 where the distance between the windows 944, 946is purposefully off center. For example, in an embodiment, the clips 216and 218 will position the sensor components off center by an approximate40%-60% split. A scoring line 1258 preferably marks this split, havingabout 40% of the distance from window 946 to window 944 as the distancebetween window 946 and the scoring line 1258. This leaves the remainingapproximately 60% of the distance between the two windows 944, 946 asthe distance between scoring line 1258 and window 944.

Scoring line 1258 preferably lines up with the tip of the nail. Theapproximately 40% distance sits atop a measurement site 426, such as thefigure shown in a generally flat configuration. The remainingapproximately 60% of the distance, that from the scoring line 1258 towindow 944, curves around the tip of the measurement site 426 and restson the underside of the measurement site. This allows windows 944,946—and thus in turn detector 176 and emitter 174—to optically alignacross measurement site 426. Scoring line 1258 aids in providing a quickand yet typically more precise guide in placing a sensor on ameasurement site 426 than previously disclosed sensors. While disclosedwith reference to a 40-60 split, the off center positioning mayadvantageously comprise some other range such as a range from an about35-about 65% split to an about 45-about 55% split. In a more preferredembodiment, window 944 to scoring line 1258 would comprise a distance ofbetween about 37.5% and about 42.5% of the total distance between window944 and 946. In the most preferred embodiment, the distance betweenwindow 944 and scoring line 1258 would be approximately 40% of the totaldistance between window 944 and window 946, as is illustrated in FIG.12. With a general 40%-60% split in this manner, the emitter anddetector should align for optimal emission and detection of energythrough the measurement site.

FIG. 13 illustrates a disposable sensor containing many of the featuresdiscussed in this disclosure such as emitter 1374 and detector 1376.Based on the disclosure herein, one of ordinary skill in the art mayadvantageously fix the components discussed herein to form a disposablesensor without moving beyond the scope of the present disclosure.

Referring again to FIG. 2, in certain circumstances, it may be desirableto replace one or more portions of the disposable 206 or reusable 204components of the sensor 102. For example, it may be advantageous toremove the base 214 (e.g., adhesive tape) portion from the disposablecomponent 206, and attach a second base portion to the remainingportions of the disposable portion, such as the first receptacle 216,the second receptacle, and/or the information element (not shown). Suchtechniques may allow the more durable and/or expensive portions of thedisposable component to be reused, reducing costs.

As such, in certain embodiments, a method of assembling a disposableattachment component of a non-invasive optical sensor is provided. Themethod can include providing a disposable attachment component of anon-invasive optical sensor, the disposable attachment componentcomprising a first flexible tape portion and at least one receptaclesupported by the first flexible tape portion and for receiving at leastone housing of a reusable component of the sensor. The reusablecomponent can include at least one energy emitter and at least onedetector capable of detecting energy attenuated by body tissue andcapable of outputting a signal usable to determine one or morephysiological characteristics of the body tissue.

The method may further include separating the first flexible tapeportion from the at least one receptacle. For example, referring to FIG.2, the base portion 214 may be cut, peeled, or otherwise separated fromthe remaining portion or portions of the sensor 206, such as thereceptacles 216, 220.

In some embodiments, the method includes attaching a second flexibletape portion to the at least one housing such that the first flexibletape portion supports the at least one housing of the reusable componentin a manner substantially similar to the manner in which the firstflexible tape portion supported the reusable component. For example,referring to FIG. 2, a second base portion (not shown) may be adhered toor otherwise coupled to the receptacles 216, 220. The second baseportion may be substantially similar in structure and/or function to thebase portion 214, for example. Such a technique provides a re-assembleddisposable component of the sensor having one or more replacedcomponents and one or more existing components.

The first and second flexible tape portions may comprise a firstaperture and a second aperture, and the method can further compriseattaching the second flexible tape portion such that the energy emittedfrom the at least one energy emitter passes through the first apertureand energy attenuated by body tissue passes through the second aperture.

In embodiments including an information element, it may also bedesirable to update and/or replace the information element in additionto replacing the tape portion. For example, the disposable attachmentcomponent may further comprise at least one information component, whichmay be any of the information elements discussed herein, and can storecompatibility information, use information, and the like. The method canfurther include separating the first flexible tape portion from the atleast one information element. In various embodiments, the informationelement resides in, or is otherwise physically associated with one ormore of the receptacles (e.g., the receptacles 216, 220 of FIG. 2, ormay alternatively be physically separate from the receptacles.

In embodiments where the information element is updated, and notreplaced, for example, the method can further include attaching thesecond flexible tape portion to the at least one information element andmodifying at least a portion of memory content of the informationelement. For example, memory locations storing use information,compatibility information, or the like, may be modified.

Where the information element is replaced, for example, the method caninclude determining at least a portion of memory contents of at leastone first information element, separating the first flexible tapeportion from the at least one first information element, and updating aportion of memory contents of at least one second information element inresponse to the at least a portion of the memory contents of the atleast one first information element. For example, use or compatibilityinformation may be transferred from the first information element to thesecond information element. The method can further include attaching thesecond flexible tape portion to the at least one second informationelement, producing a re-assembled disposable component.

Although the sensor disclosed herein with reference to preferredembodiments, the disclosure is not intended to be limited thereby.Rather, a skilled artisan will recognize from the disclosure herein awide number of alternatives for the sensor. For example, the emitter anddetector locations may be in the opposite housings from what wasdiscussed here. It is also possible that the assembly/disassembly clipand sensor clip would be reversed in relation to the casings into whichthey clip. Additionally, other combinations, omissions, substitutionsand modifications will be apparent to the skilled artisan in view of thedisclosure herein. Accordingly, the present disclosure is not intendedto be limited by the reaction of the preferred embodiments, but is to bedefined by reference to the appended claims.

Additionally, all publications, patents, and patent applicationsmentioned in this specification are herein incorporated by reference tothe same extent as if each individual publication, patent, or patentapplication was explicitly incorporated.

1. (canceled)
 2. A reusable component of a noninvasive optical sensor,the reusable component comprising: a first housing that houses anemitter or a detector and includes a locking feature; a second housingthat houses another of the emitter or the detector and includes anopening in a surface of the second housing that extends across at leasta portion of the surface of the second housing; an electrical contactaccessible through the opening in the surface of the second housing,wherein the electrical contact is configured to contact a prongextending from a disposable attachment component of the noninvasiveoptical sensor; and a flexible connector that connects the first housingto the second housing, wherein the flexible connector is configured, inresponse to mating the reusable component with the disposable attachmentcomponent and applying the noninvasive optical sensor to a tissue siteof a patient, to cause the locking feature of the first housing toengage with a corresponding locking feature of the disposable attachmentcomponent by sliding of the first housing within a receptacle of thedisposable attachment component.
 3. The reusable component of claim 2,wherein applying the noninvasive optical sensor to the tissue site ofthe patient comprises at least partially wrapping the noninvasiveoptical sensor around the tissue site of the patient and flexing theflexible connector.
 4. The reusable component of claim 3, wherein theflexible connector is further configured to cause the locking feature ofthe first housing to un-engage with the corresponding locking feature ofthe disposable attachment component in response to the noninvasiveoptical sensor being removed from the tissue site of the patient.
 5. Thereusable component of claim 4, wherein the flexible connector is furtherconfigured to un-flex in response to the noninvasive optical sensorbeing removed from the tissue site.
 6. The reusable component of claim5, wherein removing the noninvasive optical sensor from the tissue siteof the patient comprises at least partially un-wrapping the noninvasiveoptical sensor from around the tissue site of the patient.
 7. Thereusable component of claim 6, wherein the tissue site of the patientcomprises a finger or toe of the patient.
 8. The reusable component ofclaim 2, wherein the flexible connector is further configured, furtherin response to applying the noninvasive optical sensor to the tissuesite of the patient, to cause the disposable attachment component toalign at least one of the emitter and the detector on opposing sides ofthe tissue site.
 9. The reusable component of claim 2, wherein theopening in the surface of the second housing extends across at leastportions of a front surface and a bottom surface of the second housing.10. A method of using the reusable component of claim 2, comprising:mating the reusable component with the disposable attachment component;attaching the disposable attachment component having the first andsecond housings mated thereto to a patient such that the disposableattachment component is wrapped around a tissue site of the patient; andactivating the emitter to emit energy into the tissue site.
 11. Anoninvasive optical sensor comprising: a reusable component including: afirst housing that houses an emitter or a detector and includes alocking feature; a second housing that houses another of the emitter orthe detector and includes an opening in a surface of the second housingthat extends across at least a portion of the surface of the secondhousing; an electrical contact accessible through the opening in thesurface of the second housing; and a flexible connector that connectsthe first housing to the second housing; and a disposable componentincluding: a first receptacle configured to receive the first housing; asecond receptacle configured to receive the second housing, wherein thesecond receptacle includes a prong configured to contact the electricalcontact of the second housing through the opening in the surface of thesecond housing; and a corresponding locking feature, wherein theflexible connector of the reusable component is configured to engage thelocking feature of the first housing with the corresponding lockingfeature via sliding of the first housing within the first receptacle inresponse to mating the reusable component with the disposable componentand applying the noninvasive optical sensor to a tissue site of apatient.
 12. The noninvasive optical sensor of claim 11, whereinapplying the noninvasive optical sensor to the tissue site of thepatient comprises at least partially wrapping the noninvasive opticalsensor around the tissue site of the patient and flexing the flexibleconnector.
 13. The noninvasive optical sensor of claim 12, wherein theflexible connector is further configured to un-engage the lockingfeature of the first housing with the corresponding locking feature ofthe disposable component in response to the noninvasive optical sensorbeing removed from the tissue site of the patient.
 14. The noninvasiveoptical sensor of claim 13, wherein the flexible connector is furtherconfigured to un-flex in response to the noninvasive optical sensorbeing removed from the tissue site.
 15. The noninvasive optical sensorof claim 14, wherein removing the noninvasive optical sensor from thetissue site of the patient comprises at least partially un-wrapping thenoninvasive optical sensor from around the tissue site of the patient.16. The noninvasive optical sensor of claim 15, wherein the tissue siteof the patient comprises a finger or toe of the patient.
 17. Thenoninvasive optical sensor of claim 11, wherein the flexible connectoris further configured, further in response to applying the noninvasiveoptical sensor to the tissue site of the patient, to cause at least oneof the first and second receptacles of the disposable component to alignthe emitter and the detector on opposing sides of the tissue site. 18.The noninvasive optical sensor of claim 11, wherein the prong comprisesan electrically conductive protrusion configured to extend at leastpartially into the opening in the surface of the second housing inresponse to engaging the second housing with the second receptacle. 19.The noninvasive optical sensor of claim 11, wherein the opening in thesurface of the second housing extends across at least portions of afront surface and a bottom surface of the second housing.